Continuous squeezing apparatus of a rotary disc type

ABSTRACT

An apparatus for continuously squeezing liquid out of liquid containing material at a predetermined squeezing pressure having a pair of squeezing discs, each rotatably mounted on a shaft slightly inclined with respect to each other, said discs being disposed opposite to each other to define an annular groove of a V-shaped cross section between their confronting inner conical surfaces. The apparatus is provided with means for adjusting the inclination of the shafts to control the spacing of said V-shaped groove and means for supporting the respective outer ends of said shafts by a controlled supporting force for said shafts in accordance with a predetermined squeezing pressure.

United States Patent ROTARY DISC TYPE Primary Examiner-Billy J. Wilhite AttorneyKarl W. Flocks ABSTRACT: An apparatus for continuously squeezing liquid out of liquid containing material at a predetermined squeezing pressure having a pair of squeezing discs, each rotatably mounted on a shaft slightly inclined with respect to each other, said discs being disposed opposite to each other to define an annular groove of a V-shaped cross section between '3 Claims 4 Drawing Figs their confronting inner conical surfaces. The apparatus is pro- U.S. Cl 100/ 158, vided with means for adjusting the inclination of the shafts to 100/116 control the spacing of said V-shaped groove and means for Int. Cl B30b 3/04 supporting the respective outer ends of said shafts by a con- Field of Search 100/ 1 10. trolled supporting force for said shafts in accordance with a 116, 121. 158, 169, 175, 171 predetermined squeezing pressure.

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PATENTEUm Ism- 5 3,559,567

SHEET 3 OF 3 CONTINUOUS SQUEEZING APPARATUS OF A ROTARY DISC TYPE BACKGROUND OF THE INVENTION I. Field of the Invention This invention relates to a continuous squeezing apparatus, and more particularly to an improvement in the so-called V- type squeezing press, which is described hereunder.

2. Description of the Prior Art The aforementioned V-type squeezing press, generally. comprises an annular casing formed integrally with a stationary frame and having a circular plate member fixedly disposed in the annular casing concentrically thereto, a pair of circular squeezing discs each rotatably mounted on a supporting shaft.

These squeezing discs have a slightly sloped frustoconical surface at one side thereof respectively and are arranged in a manner such that the frustoconical surfaces confront each other with the central flat portions thereof being contacted with the circular plate member of the casing interposed between the discs, so that within the inner side of the casing an annular groove of a V-shaped cross section is defined between these frustoconical surfaces. Therefore, an apparatus of this type may be termed a V-press, too.

In the conventional V-type squeezing press, the supporting shafts are fixedly connected with the circular plate member at their inner ends, these shafts extending outwardly from said inner end with their axes slanted at a predetermined angle relative to each other, so that the V-shaped annular groove has the maximum widest spacing at one point and the minimum smallest spacing at a point diametrically opposite.

When the squeezing discs are rotated about the supporting shafts while being supplied with material to be processed therebetween at the widest spacing portion of the annular groove, the supplied materials are also rotated with the discs while being held therebetween and are compacted between the discs. Liquid contained in the material is extracted as the spacing portion of the V-shaped groove becomes more and more narrow. Supporting shafts of the prior type are arranged such that their axes form a fixed angle. Therefore, adjustment of the compression ratio, namely, the ratio between the maximum spacing and the minimum one was not attainable. Accordingly, the width of the minimum spacing of the V-shaped annular groove is not changeable.

The squeezing apparatus mentioned above is not capable of effectively handling various kinds of materials which differ in their liquid contents and slippage nature. In order to remove such drawbacks the present inventor has proposed a continuous squeezing apparatus with an adjustable compression ratio, which was disclosed by the present inventors Japanese Pat. No. 536991 (Japanese Patent Publication No. 19805/68, Application No. l5347/64)- I In the above-mentioned continuous squeezing apparatus, two inner ends of the supporting shafts are connected with each other at the center of the circular plate member by a pin allowing for relative rotation around the pin between these ends, while the other ends thereof are fitted in guide grooves provided at both sides of a main frame and are fixed at a selected position of the guide grooves so that ratio between the maximum spacing and the minimum one of the V-shaped annular groove may be adjusted. Thus, the compression ratio of the apparatus can be adjusted at a desired value before starting, depending upon the liquid content of the materials to be processed. However, since in the squeezing apparatus mentioned above, the adjustment of the compression ratio is not obtainable during its operation, it has proved to be effective for processing materials only when the conditions of the squeezing operation, that is, the liquid contents and slippage nature of the materials and the feed ratio thereof, etc. are maintained constant throughout during the squeezing operation. On the other hand, if the conditions of supplied materials are changed in the continuous operation so that the materials become of less liquid content and/or of a less slippage nature, the materials are liable to be fed excessively between the squeezing discs. As a result. when materials are supplied excessively in regard to the predetermined compression ratio, they are still forced into the portion where both discs take their position of minimum spacing. Since the compression ratio of such squeezing apparatus is fixed to be constant during the operation, the squeezing discs will be forced to apply excessive force beyond the predetermined compressing force upon the material interposed therebetween. Thus excessive force will be transmitted to the supporting shafts of the discs and in turn to the means supporting the shafts with the result that the apparatus is often damaged. Therefore, in these cases the compression ratio has been obliged to be preset at a relatively smaller value while making the width of the minimum spacing of V-shaped annular groove larger. However, in the middle way of its continuous squeezing operation with the aforementioned relatively smaller compression ratio being maintained, if the conditions of the supplied materials are changed to have a greater liquid content and become more slippery in nature, the minimum spacing of the annular groove will be too wide to carry out the desired squeezing.

The apparatus of the present invention is constructed so as to eliminate the occurence of such damage, due to the change of the condition of the supplied materials and that of insufficient squeezing due to the minimum spacing of the annular groove being made wider, even in the above-mentioned situations, that is, each external end of the supporting shafts is controllably received by a suitable shaft end supporting means, so that the reaction forces created by the material on the squeezing discs are resiliently borne through said supporting means.

Due to this novel construction, squeezing or dehydration can be carried out at a constant compacting pressure even in instances where excessive or too little material is supplied.

In an apparatus of this kind naturally an increasingly larger capacity is demanded from an economical point of view. Therefore, it is necessary to increase the number of revolutions of said discs and adjust the inclination of the shafts depending on the nature of the materials to be processed so as to increase the squeezing capacity of the apparatus by supplying as large a quantity of materials as possible.

According to the present invention, not only various kinds of materials can be squeezed continuously and very effectively by setting the apparatus to a correct compression ratio, but also they can be squeezed at a predetermined pressure by supporting the outer ends of the supporting shafts by a controlled force, even in a case where the conditions of the supplied material are changed during the operation.

SUMMARY OF THE INVENTION The present invention has as its object the provision of an apparatus for completely and controllably effecting continuous squeezing of liquid from solid material containing liquids at a constant pressure, regardless of their liquid content and slippage nature.

BRIEF EXPLANATION OF THE DRAWINGS FIG. 1 is a sectional view of a squeezing apparatus according to the presentinvention taken along line 1-1 of FIG. 2;

FIG. 2 is a side elevation of the present invention;

FIG. 3 is a sectional side elevation of the squeezing apparatus according to the present invention; and

FIG. 4 is a schematic view illustrating another embodiment of the present invention DESCRIPTION OF THE PREFERRED EIVIBODIMENTS An outer annular casing 1 is integrally formed with a frame F, the inner surface thereof defines a part of a spherical surface having a certain breadth symmetrical with reference to the median plane of the sphere. In the sectional view shown in FIG. 1 the aforementioned inner surface is depicted as two opposing arcs. A circular plate member 2 concentrically disposed in the inner space of the annular casing is fixed at the forward end of an arm plate 3 (see FIG. 3) which is formed intcgrally with the annular casing I to extend radially inwardly from the inner surface of the casing. The outer peripheral surface of the circular plate member 2 defines a middle portion of a sphere slantingly sliced symmetrically with reference to the median plane thereof concentrically with the inner surface of the annular casing so that one of the diametrically opposite ends of the plate member is slightly thicker than the other end. A rectangular opening 4 is (see FIG. 3) provided at the center of the circular plate member 2 with the two opposite sides of the rectangular opening slanted with respect to the horizontal plane. In the opening 4 the inner ends of supporting shafts 5, 6 are housed. One of said supporting shafts S has a forked end which engages with an outwardly extended end of the other shaft 6 and are pivotally connected by a pin 7. The pin 7 is located at the center of the opening to extend longitudinally therethrough both end portions thereof being inserted in the bore provided in the circular plate member 2. Consequently, shafts 5, 6 are able to pivot relative to each other about the pin 7.

8, 9 denote a pair of opposing squeezing discs each having a number of perforations. Hollow shafts 10, 11 are formed integrally with the discs at the rear surface thereof and fitted on the supporting shafts 5, 6, thereby the squeezing discs rotatably supported about said supporting shafts.

Each of the front surfaces of the squeezing discs is formed in a slightly inclined frustoconical shape and annular recesses 12 and 13 are provided at the central portions of the squeezing discs, respectively. The two annular recesses 12 and 13 receive both the side surfaces of the circular plate member and engage loosely with the outer spherical surface thereof. The outer peripheral surface of each squeezing disc 8 or 9 is placed close to the inner spherical surface of the annular casing when they are assembled.

Sprockets I4, 15 are firmly fixed on the hollow shafts 10, 1 1.

Upright side frames 17-17 are formed integrally with and at both sides of a frame F, on which side frame portions 18-18 for supporting the outer ends of the shafts 5, 6 respectively are tightly fixed by welding or any other suitable means.

Guide groove 19 (see FIG. 2) is provided within each side frame portion 18 with its parallel guide surfaces incline obliquely with respect to the horizontal plane.

An outer end of each supporting shaft 5, 6 is fitted in the guide grooves 19 and carries an adjusting screw 20 screwed therein. The end of the screw extends through the end of the supporting shaft and contacts with the inside surface of the lower end of the guide groove 19, and the other end, namely, the head of the adjusting screw extends above the upper surface of the supporting shaft.

To the inside surface of the upper end of each guide groove is attached a shaft end supporting means consisting of a cylinder 21 and a piston 22 housed therein. The cylinders 21 are removably provided in the guide grooves respectively. The forward end of the piston abuts the head of the adjusting screw 20.

An inlet pipe 23 for supplying pressurized fluid such as oil or air is connected at its one end to the rear end of the cylinder and to an oil pump or air compressor at the opposite end. At least one pressure gauge 24 and an accumulator 25 are also connected to the pipe line.

The supporting shafts 5, 6 are rotatably connected with each other at their inner ends by pin 7. and extend obliquely and downwardly toward the side frame portions 18-18 fixed right and left side of the frame F respectively. As the guide grooves 19 are provided in a manner such that the longitudinal length thereof are slanted at an angle respectively corresponding to the inclination of a plane in which the respective axis of the supporting shafts moves, the outer ends of the shafts 5, 6 will slide within the respective guide grooves longitudinally along the inner wall surface thereof when the shafts 5, 6 moves pivotally around the connecting pin 7.

Since the supporting shafts 5, 6 extend obliquely and downwardly as mentioned before, the V-shaped annular groove defined by the two opposing squeezing discs has minimum spacing at its lower slantwise position of the V- shaped groove and maximum spacing at the diametrically opposite position of the groove at which material to be processed is supplied.

Sprocket 14. 15 mounted on each hollow shaft of the squeezing discs are driven by endless chains 28-28 trained thereon and also over other sprockets 30-30 mounted on the driving shaft 29 respectively (see FIGS. 2 and 3).

An opening is provided in the annular casing l at the location where the squeezing discs have the widest spacing and is connected to a feeding hopper provided thereon.

A discharging chute 32 is also mounted on a position a little above the portion where the squeezing discs have the minimum spacing. A suitable scraping plate 33 is also provided at that portion.

In operation, the inclination of the supporting shafts is adjusted by turning the adjusting screws 20-20 to set the ratio between maximum spacing and minimum one of the V-shaped groove on the diametrically opposite positions thereof at a predetermined value. When material of very low liquid content is processed, the volume change between before and after squeezing will be comparatively small so that the supporting shafts are arranged to have a comparatively small inclination angle so as to make the aforesaid ratio small. Whereas in case the material contains considerable amounts of liquid, the inclination of the supporting shafts if adjusted to set the aforesaid ratio at a greater value.

Subsequent to the adjustment of the spacing, the oil pump or the compressor is started to supply a pressurized fluid into the cylinder 21-21 and the accumulator 25, the pistons 22-22 are pushed forward and each front end of the piston abuts the head of the associated adjusting screw 20. When the applied fluid pressure reaches a predetermined value, the supply of the fluid is stopped by closing the stop valve 27.

As the pistons act to oppose the reaction effected by the material being compacted between said two squeezing discs, the pressure acting on the materials to be squeezed can be controlled by adjusting the pressure of the pressurized fluid introduced within the cylinders. The percentage of liquid contents of the materials after having been squeezed is determined by the squeezing pressure applied thereto which depends on the pressure of the fluid within the cylinders forcing the associated pistons to support the ends of the supporting shafts 5, 6 respectively.

Firstly, a preliminary operation is carried out by setting the aforesaid pressure of fluid at a suitable value to get a desirable percentage of liquid contents of the squeezed material, by rotating the squeezing discs 8, 9 while supplying the material to be squeezed therebetween. In this case, if the width of the minimum spacing of the V-shaped annular groove is too large, namely, the compression ratio is too small in regard to the condition of the material such as the amount of liquid contents of the material and/or the slippage nature thereof, the piston will push against the head of the screw 20 forcing the end thereof to bear against the lower end of the guide groove since the reaction effected by the material being compacted is smaller than the supporting force by the pistons which depends on the predetermined pressure of the pressurized fluid. Then, the previously set width of the minimum spacing is adjusted to become smaller by turning the adjusting screws 20-20 so that the compression ratio is adjusted to become bigger and to approach a proper ratio such as explained hereunder. As the width of the minimum spacing becomes smaller the reaction of the compressed material becomes larger, and when the spacing is adjusted to the proper amount for the material to be processed, the piston will be pushed back and maintained at a position within the cylinder to balance with the reaction of the compressed material with the end of the screw 20 being just clear of the lower end or bottom of the guide groove without causing any obstacles during the operation with normal amounts of supply of material. If the compression ratio is set at a value much greater than the aforesaid proper ratio. and especially in case too large a compression ratio is taken for the material of less liquid contents and less slippage nature. the following obstacles will occur. even if the aforesaid proper pressure of fluid is kept: In case such material is processed, the reaction caused by the material compacted between the opposing discs sometimes becomes extremely large in the midway of the angular path along which the supplied material is moved in the rotation of the squeezing discs while being compacted therebetween from the initial location at which the spacing between the discs is maximum towards the location at which said spacing is minimum, that is. at a point located at an angle of about 90 from the aforementioned initial location. In such case, since the reaction caused by the compressed material at said point acts against the lateral wall of the guide groove substantially perpendicularly thereto without being hydraulically supportedby the ends of the pistons. Thus, the ends of the supporting shafts are fixedly supported by the lateral wall of the guide groove, with the result that the guide groove will sometimes be damaged.

Once the suitable fluid pressure and compression ratio are determined as explained above, the squeezing apparatus is ready for normal continuous operation.

Materials are supplied and are rotated being kept between the squeezing discs and transferred to the position of narrower spacing while being compacted between said two squeezing discs. As the spacing of the discs become more narrow, the materials are compacted more tightly, liquid contained therein is extracted through the perforations 16 of the discs and the squeezed dregs are removed from the apparatus by means of a scraping plate 33.

In case a variation of the conditions of material supply such as an increase of supply rate or a decrease of liquid content of the fed material takes place, the squeezing discs are forced to spread their minimum spacing by pushing the outer ends of the supporting shafts obliquely and upwardly to urge the piston against the fluid pressure applied thereto. The piston thus suppressed forces the oil within the cylinder to flow backward to the accumulator, whereby the oil pressure within the cylinder will rise but only very slightly, so there will be brought about no substantialvariation in compressive force at the minimum spacing portion of the annular groove. As a result, the materials are still squeezed under substantially normal conditions.

The apparatus of this embodiment comprising means for supporting the ends of the shafts 5, 6 including pistons, oil pumps and an accumulator has many advantages in that the pressure control in said supporting means is easily obtainable, that the pressure for supporting the shaft ends can be controlled within a wide range and large pressure is easily obtainable, and that the apparatus has high efficiency.

FIG. 4 refers to another embodiment of the present invention suitable for handling materials which necessitate a smaller compacting force but which involves a lower installation cost.

Adjusting screws -20 are threaded into the outer ends of the supporting shafts 5, 6 respectively. The head of each of the adjusting screw 20 is engaged by the forward end of an adjusting bolt 40. On the threaded portion of the adjusting bolt 40 is fitted the adjusting nut 41 which is resiliently biased downwards by a compression spring 43 provided between said nut and the lower surface of the side frame portion 18.

Adjustment of the spring force is effected by turning the adjusting nut 41 without making any change in the location of the forward end of the adjusting bolt 40.

In this embodiment, the supporting force is relatively small. Therefore, turning thereof is effected manually. The first embodiment utilizing the pressurized supporting means such as cylinder, piston and oil pump as well as the second embodiment utilizing a spring adjustment are both directed to support the shaft end with a constant pressure under normal operation and also to adjust the squeezing pressure depending on the nature of the material to be processed.

it is to be understood that this invention may include within the scope of the t present invention other embodiments which perform similar unctions. From the foregoing dCSCIlptIOI'l, it

will be appreciated that this invention has distinguishable advantages over squeezing apparatuses of the prior art by enabling the user to adjust the V-shaped groove at the optimum ratio between maximum spacing and minimum spacing in accordance with the nature of the materials to be processed. Furthermore, it also enables to adjust the force applied to outer ends of the shafts to automatically keep the squeezing pressure at a predetermined value in case the shaft ends are apt to be pushed back by the supplied material, so that a continuous squeezing operation may be carried out satisfactorily even when there happens any variation either in its supply rate or in the nature of the material during the course of the squeezing operation.

I claim:

1. A continuous squeezing apparatus of the rotary disc type comprising an annular casing formed integrally with a stationary frame and having a circular plate member concentrically and fixedly disposed in said casing, the inner surface of said annular casing defining a part of a spherical surface having a certain breadth symmetrical with reference to the median plane of the sphere, the outer peripheral surface of said circular plate member forming a part of a spherical surface concentric with said spherical surface of the inner wall of said annular casing, a pair of squeezing discs each rotatably mounted on a shaft and having a frustoconical surface at one side thereof, said frustoconical surfaces confronting each other to define within the inner side of said casing an annular groove of V-shaped cross section therebetween, said shafts being pivotally connected with each other at their inner ends with said ends received in a central opening of said circular plate member and each extending outwardly from said inner end with its axis slanted relative to the axis of said annular casing, side frame portions of said frame disposed on the opposite sides of said annular casing and each having a guide groove within which the outer end of the associated shaft is adapted to be slidably received, means provided at said outer ends of said shafts respectively for adjusting the slanting angle of each of said axis of said shafts to thereby control the spacing of said V-shaped groove, and means disposed in each of said guide grooves to engage said first-mentioned means and support said outer end of the associated shaft, said last-mentioned means being capable of supporting said end of the associated shaft by a force controlled to maintain the squeezing pressure at a predetennined value.

2. A continuous squeezing apparatus of the rotary disc type according to claim 1, in which said last-mentioned supporting means includes a fluid-actuated piston-cylinder assembly, and said first-mentioned adjusting means includes a screw adjustably threaded into said outer end of each of shafts with one end of said screw abutting against the forward end of said piston while the other end of said screw abuts against an inner end surface of said associated guide groove opposing said forward end of said piston.

3. A continuous squeezing apparatus of the rotary disc type according to claim 1, in which said last-mentioned supporting means includes a bolt inserted in a bore provided in a wall of said frame, spring means for urging said bolt towards said firstmentioned adjusting means and a nut engaged with said bolt to adjust the resilient strength of said spring, and said first-mentioned adjusting means includes a screw adjustably threaded into said outer end of each of said shafts with one end of said screw abutting against the end of said bolt while the other end of said screw abuts against an inner end surface of said associated guide groove opposing said end of said bolt. 

1. A continuous squeezing apparatus of the rotary disc type comprising an annular casing formed integrally with a stationary frame and having a circular plate member concentrically and fixedly disposed in said casing, the inner surface of said annular casing defining a part of a spherical surface having a certain breadth symmetrical with reference to the median plane of the sphere, the outer peripheral surface of said circular plate member forming a part of a spherical surface concentric with said spherical surface of the inner wall of said annular casing, a pair of squeezing discs each rotatably mounted on a shaft and having a frustoconical surface at one side thereof, said frustoconical surfaces confronting each other to define within the inner side of said casing an annular groove of V-shaped cross section therebetween, said shafts being pivotally connected with each other at their inner ends with said ends received in a central opening of said circular plate member and each extending outwardly from said inner end with its axis slanted relative to the axis of said annular casing, side frame portions Of said frame disposed on the opposite sides of said annular casing and each having a guide groove within which the outer end of the associated shaft is adapted to be slidably received, means provided at said outer ends of said shafts respectively for adjusting the slanting angle of each of said axis of said shafts to thereby control the spacing of said V-shaped groove, and means disposed in each of said guide grooves to engage said firstmentioned means and support said outer end of the associated shaft, said last-mentioned means being capable of supporting said end of the associated shaft by a force controlled to maintain the squeezing pressure at a predetermined value.
 2. A continuous squeezing apparatus of the rotary disc type according to claim 1, in which said last-mentioned supporting means includes a fluid-actuated piston-cylinder assembly, and said first-mentioned adjusting means includes a screw adjustably threaded into said outer end of each of shafts with one end of said screw abutting against the forward end of said piston while the other end of said screw abuts against an inner end surface of said associated guide groove opposing said forward end of said piston.
 3. A continuous squeezing apparatus of the rotary disc type according to claim 1, in which said last-mentioned supporting means includes a bolt inserted in a bore provided in a wall of said frame, spring means for urging said bolt towards said first-mentioned adjusting means and a nut engaged with said bolt to adjust the resilient strength of said spring, and said first-mentioned adjusting means includes a screw adjustably threaded into said outer end of each of said shafts with one end of said screw abutting against the end of said bolt while the other end of said screw abuts against an inner end surface of said associated guide groove opposing said end of said bolt. 